In the 3rd Generation Partnership Project (3GPP), a radio access method and a radio network for cellular mobile communications (hereinafter, referred to as “Long Term Evolution (LTE)”, or “Evolved Universal Terrestrial Radio Access (EUTRA)”) have been studied. In LTE, a base station device is also referred to as an evolved NodeB (eNodeB), and a terminal device is also referred to as a User Equipment (UE). LTE is a cellular communication system in which multiple areas each covered by the base station device are deployed to form a cellular structure. A single base station device may manage multiple cells.
In 3GPP, career aggregation has been specified which allows a terminal device to perform simultaneous transmission and/or reception in multiple serving cells (component careers).
NPL 1 proposes configuring, for each serving cell and aggregation level, the number of PDCCH candidates included in a User Equipment-specific Search Space (USS) monitored by a terminal device. Furthermore, NPL 1 proposes introducing, for each serving cell, deactivation of monitoring of a DCI format 0/1A.